The Sinister Syndicate's original incarnation consisted of the Beetle, Rhino, Speed Demon, Hydro-Man & Boomerang. They battled Spider-Man, Silver Sable & the Sandman at Coney Island.
The Syndicate originally were hired by the criminal mercenary Jack O'Lantern (Macendale) to kill Spider-Man and Silver Sable. Most of how the five criminals came together is unrevealed, but there is a strong possibility most of them knew each other from working as hired muscle for Justin Hammer. They ambushed Spider-Man and Sable at Coney Island, and almost succeeded on their first assignment, if it were not for the timely intervention of the recently reformed Spider-Man foe the Sandman, who was boarding up with a family that lived nearby and was licking his chops to trade blows with Syndicate member Hydro-Man, who was a hated enemy. Despite this setback, all five of the criminals managed to escape. In the end, the long lasting effects of the attack were a concussion for Spidey thanks to a charging Rhino, Two sprained ankles for Silver Sable who foolishly tried to knock out the armored Beetle using a well placed diving kick and the destruction of the world famous roller coaster the Cyclone, which has since been rebuilt.
With their reputation now in question, the group next took an assignment in the small Balkan country of Belgriun working for fellow Spider-Man enemy Doctor Octopus to help overthrow the Monarch of the country and in doing so posing as heroes of the people. Already you can see the foreshadowing of things to come for the group, such as in-fighting and selfish arrogance. The Beetle shows signs of doubt about his role as a villain, and Boomerang clearly questions the Beetle's leadership of the group every step of the way, thinking himself to be a better choice to lead. The Speed Demon is clearly trying to push the rest of the team's buttons especially Boomerang and Hydro-Man. Spider-Man, Silver Sable and the Sandman, now working freelance for Sable, all are dispatched to Belgriun to take down the Syndicate. Early on the Syndicate gain the upper hand, attacking Spidey and chaining him down. This victory, however, is short lived as Spidey takes out Boomerang first, then Sable takes down Hydro-Man and Sandman defeats the Rhino. With the assignment a bust, the Beetle manages to barely escape as does Speed Demon. Hydro-Man suffered an electrocution at the hands of a falling chandelier and is either captured or reforms himself later and manages to escape. The Rhino was knocked unconscious by the Sandman and is presumably taken into custody. Boomerang was slipped knock out gas by Sable(done off panel) and taken to a local hospital. It is presumed he is then arrested.
After the group takes a hiatus to pursue solo ventures, the group once again is reformed by the Beetle, who having been recently released from prison and in debt to such figures as the Kingpin and the Tinkerer, needs the extra muscle to succeed in paying them back. From the get-go, Boomerang once again tries to stir the pot and reminds The Beetle of their past failures under his leadership. Rhino keeps the peace and tells Boomerang to be quiet and listen to Jenkins. The group then plan a bank robbery which is interrupted by Spider-Man. The group quickly gain the upper hand on the wall crawler and actually are about to deliver the killing blow when the Rhino steps in and lets the others know he does not want to be an accessory to murder as he only wants to make enough money so he can remove his hide, which is now permanently bonded to his body. The group begrudgingly agrees and moves on with the escape. However, Boomerang decides to go back inside the bank to finish the job and ends up being captured by Spider-Man. Leila Davis, who Boomerang was dating at the time, served as the Syndicate's get away driver and the Beetle forces her to drive away due to the swarm of cops and Boomerang's defiance. Soon, the others learn about the Beetle's debts and how the first heist was entirely owed and taken by the Kingpin. This now puts a damper on the groups loyalty to Jenkins, but they agree to let him live. The group then decides their next course of action, either attempt to spring Boomerang from prison or hire a lawyer for him.
After an unsuccessful attempt to spring Boomerang from prison, The Beetle begins to show a lack of confidence in his abilities to lead the Syndicate in front of Boomerang's girlfriend Leila Davis, who secretly has an ulterior motive to joining up with the group: revenge on the Beetle for humiliating her husband, Anthony Davis. Davis was also known as the deceased super criminal the Ringer, who the Beetle used as a pawn in a scheme to defeat Spider-Man. He was murdered by the Scourge of the Underworld but Leila believed it would never have happened if Beetle hadn't made him feel so useless. After a vote by the rest of the team, the majority agree to hire Boomerang a lawyer. The name of the lawyer is Mr. Partridge, whom Jenkins had used in previous incarcerations. During this time the group is beginning to take shape. Speed Demon secretly goes to the Beetle, asking if maybe he could deliberately sabotage Boomerang's case, with the Beetle commenting that he is aware that Speed Demon is clearly trying to put the moves on Leila.The Rhino is promising after one last big score he will leave the team, a move that the Beetle realizes he cannot afford. The aimless Hydro Man is clearly just in it for the wealth and power and strikes up a friendship with the Speed Demon. The next heist the Syndicate pull is an armored car theft, which is highly successful. Behind the scenes, Leila Davis visits the Kingpin to see what she can do to correct her boyfriend's situation. Boomerang's lawyer Partridge deliberately sabotages his case in court, and the Syndicate move in to free him. They are unsuccessful in their attempt to free him in a court room brawl however, and barely manage to escape amidst the timely intervention of Spider-Man and a group of Guardsmen.